Envelope



Nov. 12, 1929. B. R. HARRIS 1,735,273

ENVELOPE FiIed June 1s, 1924v Patented Nov. 12, 1929 UNITED STATESBENJAMIN R, HARRIS,

or c aroAGo, ILLINOIS,

ENVELOPE. i

Application filed June 13,

This invention relates to envelopes, and has for its object to provide anew and improved device of this description.

One of the objects of the invention is to so treat the envelope or thepaper used for the manufacture of the envelope chemically ormechanically or bot-h, so that the opening of a letter received in themails is simplified, and so that danger of accidental tearing of the1nclosed documents are prevented.

The invention has a further object to provide an envelope that shows atear after the sealed envelope has once been opened.

The invention has further objects which are more particularly pointedout in the accompanying descriptions.

Referring now to the accompanying drawing,

Fig. 1 is'a view of one form of envelope embodying the invention.

Fig. 2 is a view showing the envelope before the parts are folded.

Fig. 3 is a view showing a modified construction.

Fig. 4 is a view showing a further modified construction.

Referring now toth'e drawings, I have shown in Fig. 1 an envelopeembodying the invention sealed ready to be opened by the receiver. Theenvelope is made in the ordinary way from a blank having the top andbottom folds land 2, the end pieces or folds 3 and 4t attached to thecentral portion 5, such envelope being shown in Fig. 2 before it isfolded into the position shown in Fig. 1, the

top and bottom and end pieces being folded over to complete theenvelope.

In carrying out my invention I weaken the material of the envelope atacertain point or points so that when the envelope is opened the materialwill be torn at the weakened point or points. I may weaken this materialeither chemically or mechanically.

In carrying out my invention I applyan adhesive 6 to the edge 7, 8 ofthe fold 2. I also apply adhesive 9 to the edge 10 and 11 of the fold 1and along a portion of the edge 11, 12 of the fold 1, leaving a portionof such edge free from adhesive material. The fold 2 or the fold 3 isweakened at the edge in 1924. Serial No. 719,710.

any desired manner, as, for example, by the application of some suitablechemical such as acid oralkali or an acid salt'or a combination of asuitable acid with a salt. This weakening chemical is applied to asuitable hydrochloric acid with a moderate amount of zinc chloride, orsodium or potassium hydroxide solution or sulphuric acid or any otherweakening chemical. The chemical is properly diluted so as not todestroy the material of the envelope, but simply weakens it. I havefound, for example, that a 37 per cent hydrochloric acid ma 5 to 10. percent perchloric acid or a to 4 per cent sodium of potassium hydroxide orsulphuric acid will secure good results. Any of the usual adhesives maybe used, such as ordinary en- ,Velope glue, casein glue, resin gum orrubber cements and the like.

- Locationof the weakened part 14 may, of

course, be varied, but I prefer to'have it son'iewherc nearthe middle ofthe edge 7, 13 of the fold 2. Instead of using a chemical to weaken thematerial of the envelope I may weaken it mechanically, as forexample, byremoving a portion of the material by forming a slot, a series ofperforations or the like.

In Fig. 2 I have shown the fold 3 provided with a slot 15. slot, asshown in Fig. 2 I may use any other weakening constriilction; I haveshown two other forms, namely, the form 16 of Fig. 3 and 17 of Fig. 4.In each case the adhesive is applied preferably in the process ofmanufacture of the envelope to a iortion of the fold in proximity to theweakened portion, or on the fold which is engaged by the fold having theweakened portion. In Fig. 2 I have shown the fold 3 as being providedwith the adhesive 18 near its edge, and this adhesive will be used ifthere is no mechanical weakening of thefold 3, but said fold 3 or thefold 2 ischeinically weakened.

In Fig. 3 I have shown the adhesive 19, in

Instead of using a simple a Fig. 4 adhesive 20. The adhesive 18 to 20 ispreferably placed on the outside of the material of the envelope. Thesender moistens the adhesive area 18, 19 or 20 and presses the fold 2down upon it, the fold 3 being folded over on the central portion 5, andthen seals the fold 1 in the usual manner. When the receiver receivesthe envelope he opens it by inserting a finger or any other openingdevice between the folds 2 and 3 at 21, Fig. 1 and forces his fingertoward the fold 1. This causes a tear in the fold 3 or 2 depending uponwhich is weakened, and the envelope is thus easily and quickly openedw'thout any danger of tearing the documents as is often done when theenvelope is opened in the usual way by an opener which cuts or tears theedge 22, Fig. 1.

It will also be seen that the envelope shows positive evidence that ithas been opened, such evidence being the tear in the fold 2 or It willbe noted that the portions of the envelope that are weakened on thediagonally extending edge either of the side fold or the end fold andthat the envelope is not opened at the top as is usually done but isopened along the adjacent diagonally extending edges; that is, theopening device, either the finger or anything used for this purpose, isinserted as clearly shown in Fig 1 at the point 21 where thesediagonally extending edges meet.

I claim:.

1. An envelope adapted to be closed at one point and opened 'at anotherpoint comprising a central portion, two side folds and two end foldsfolded thereon to form the complete envelope, one of said side foldsbeing the I closing point and one of said end folds being the openingpoint, the material near the edge of said end "fold being weakened, aportion of such edge being free from adhesive material, another portionof the edge being connected by adhesive material to one of the sidefolds whereby, when an opening device is inserted between the side foldand the end fold the material near the edge of which is weakened, toopen the envelope, the material of the end fold is torn.

2. An envelope in which the enclosure is inserted at one site andremoved from the other end, comprising a central portion having two sidefolds and two end folds adapted to be folded on the central portion soas to provide edges extending diagonally across.

the envelope, means for fastening all of said folds together permanentlywhen the envelope is sealed, one of the end folds being weakened alongits diagonally extending edge so as to tear when an opening device isinserted between the said weakened end fold and the adjacent side fold.

Signed Chicago, county of Cook, and State of Illinois, this Q th day ofMay, 192

BENJAMEN R. HARRIS.

